Re: synchronized_standby_slots behavior inconsistent with quorum-based synchronous replication

Hi Alexnader,

On Thu, Feb 26, 2026 at 1:29 AM Alexander Kukushkin <cyberdemn@gmail.com>
wrote:

> Hi,
>
> On Thu, 26 Feb 2026 at 09:45, shveta malik <shveta.malik@gmail.com> wrote:
>
>>
>> As suggested in [1], IMO, it is a reasonably good idea for
>> 'synchronized_standby_slots' to DEFAULT to the value of
>> 'synchronous_standby_names'. That way, even if the user missed to
>> configure 'synchronized_standby_slots' explicitly, we would still have
>> reasonable protection in place.
>
>
> Hmm.
> synchronous_standby_names contains application_names,
> while synchronized_standby_slots contains names of physical replication
> slots.
> These are two different things, and in fact sync replication doesn't even
> require to use replication slots.
> What is worse, even when all standbys use physical replication slots there
> is no guarantee that values in synchronous_standby_names will match
> physical slot names
>

That's right, thanks for reminding me. I am convinced that we can't use the
defaults of synchronous_standby_names for synchronized_standby_slots. What
do you think about the rest of the proposal?

Thanks,
Satya